Web 3.0 is a widely-misunderstood term which seems to refer to an imagined third generation of the web. Experts say Web 3.0 is about creating a more interconnected web which will probably include the semantic tagging of content. Many of the same web experts suggest that Web 2.0 is at a "mature stage" and that we are well into Web 3.0. Web 3.0, an extension of the current web, refers to a third period of development and is best understood as the third decade of web development from 2010-2020.
Web 3.0 and the semantic web are often used as synonyms because they share some of the same concepts and ideals. We prefer to think of the semantic web as a set of trends and technologies that will reach maturity during Web 3.0. Some web watchers argue that Web 2.0 is in an intermediate stage and others dismiss it (and the use of Web 1.0, Web 2.0, etc.).
It is unsurprising that Web 3.0 would be met with controversy. Web versioning incites debate even annoyance. Nonetheless our goal with Web 3.0 should be on how to organize documents with more precision so that we can find them.